CN109913287B - Tetraurea lubricating grease and preparation method thereof - Google Patents
Tetraurea lubricating grease and preparation method thereof Download PDFInfo
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Abstract
The invention provides a tetraurea lubricating grease and a preparation method thereof. The tetraurea lubricating grease comprises the following components in percentage by mass: 7-15% of a tetraurea thickening agent, 85-93% of base oil and various additives. Mixing 35% of base oil and diisocyanate, heating to 60-80 ℃, and dissolving the materials; simultaneously, mixing and heating 40% of base oil, monoamine and diamine to 80-100 ℃ to enable amine liquid to be uniformly dissolved and have no granular feeling; mixing the two oil solutions at the temperature of 90-110 ℃ for reaction; heating the mixture to 140-160 ℃; adding 25% of base oil into the mixture for cooling, and cooling the mixture to 120-140 ℃; continuously heating the mixture to 200-220 ℃; adding additive when the mixture is cooled, and grinding into grease. The tetraurea lubricating grease has excellent comprehensive performance and more outstanding high temperature, and meets the lubricating requirements of harsh parts in the industries of metallurgy, mining, textile, food, printing and dyeing, papermaking and the like.
Description
Technical Field
The invention relates to a lubricant, in particular to a tetraurea lubricating grease and a preparation method thereof.
Background
Polyurea lubricating grease is a common lubricant and is widely applied to various mechanical equipment. On the basis of all grease production statistics worldwide, polyurea-based greases account for approximately 6%, with production areas dominated by japan, north america, europe, and china. The polyurea lubricating grease has good comprehensive performance, particularly has excellent service life and thermal stability, can meet different use requirements, is suitable for occasions with high and low temperature, high and low load, high and low speed and poor medium contact, and is widely applied to industries such as metallurgy, automobiles, food, precision bearings, papermaking and the like.
The polyurea thickening agent belongs to an organic thickening agent, and a system is very stable under the combined action of hydrogen bonds and van der Waals force. Polyurea greases are largely classified into diurea greases and tetraurea greases depending on the number of urea groups in the thickener. Diurea is the most developed, the most produced, and the most widely used variety. However, the diurea grease is easy to harden at high temperature, blocks pipelines, and brings poor lubrication and potential safety hazards to equipment, and meanwhile, the water resistance and the roller stability of the diurea grease are general, and the application effect in a humid environment is not ideal. At present, the tetraurea is a novel variety, has strong thickening capability and outstanding high-temperature performance, but related reports are few. CN102382707A is pure tetraurea lubricating grease, and the types of the used raw materials organic amines are different. CN102417855A et al refer to tetraurea grease, but mainly highlights the compounding technique, and the type of organic amine used as the raw material of the tetraurea grease is also different. Therefore, the development of the novel tetraurea lubricating grease is mainly to find and utilize new raw materials and new processes to obtain products with more excellent performance, and meanwhile, a new additive system and a new composite technology are also deeply researched to develop the tetraurea lubricating grease with excellent comprehensive performance.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a tetraurea lubricating grease and a preparation method thereof.
The technical scheme of the invention is as follows:
the invention relates to a tetraurea lubricating grease, which comprises a tetraurea thickening agent and base oil; the components and the parts by mass are as follows: 7-15% of a tetraurea thickening agent and 85-93% of base oil.
Various additives may be added to the tetraurea grease of the present invention.
The tetraurea thickener is a reaction product of a monoamine, a diamine, and a diisocyanate, wherein the weight ratio of monoamine: diamine (b): the molar ratio of the diisocyanate is 2:1:2, and the structural general formula is as follows:
wherein R is1Represents the end group of a monoamine, R2Represents a diisocyanateIntermediate group of (3), R3Represents a diamine intermediate group.
The monoamine refers to at least one of aliphatic amine, alicyclic amine and aromatic amine, and has a structural general formula of R1-NH2(ii) a Wherein the aliphatic amine is R1Is a carbon number C12～C18The normal alkyl monoamines and the alicyclic amines are R1Being cyclohexyl or cyclopentyl monoamine, aromatic amine means R1Is phenyl or substituted phenyl monoamine; the preferred monoamine is dodecylamine (n-C)12H25NH2) Decatetramine (n-C)14H29NH2) Hexadecylamine (n-C)16H33NH2) Octadecylamine (n-C)18H37NH2) Or at least one of cyclopentylamine, cyclohexylamine, aniline and p-toluidine; the most preferred monoamine is octadecylamine.
The diamine refers to alicyclic diamine with a structural general formula of H2N-R3-NH2. Alicyclic diamines are defined as R3Diamines which are single or two cyclopentyl or cyclohexyl groups; the preferable diamine is at least one of 1, 3-cyclopentediamine, 1, 2-cyclohexanediamine, and 4, 4' -dicyclohexylmethanediamine; the most preferred diamine is 4, 4' -dicyclohexylmethanediamine.
The diisocyanate refers to aliphatic diisocyanate, alicyclic diisocyanate and aromatic diisocyanate, and the structural general formula is as follows: ONC-R2-CNO; preferred diisocyanates are 4,4 '-diphenylmethane diisocyanate (MDI), Toluene Diisocyanate (TDI), 1, 4-cyclohexane diisocyanate, p-phenylene diisocyanate, 4' -dicyclohexylmethane diisocyanate (H)12MDI), 1, 6-hexamethylene diisocyanate; the most preferred diisocyanate is MDI.
The base oil refers to mineral oil, synthetic oil, vegetable oil or a mixture of the mineral oil, and the preferred base oil refers to mineral oil.
The synthetic oil refers to Poly Alpha Olefin (PAO), ester oil, alkyl naphthalene or a mixture of the above.
The additive is antioxidant, antirust agent, extreme pressure agent, antiwear agent or their mixture.
The preparation method of the tetraurea lubricating grease comprises the following steps:
(1) mixing 35% of base oil and diisocyanate, heating to 60-80 ℃, and dissolving the materials; simultaneously, mixing and heating 40% of base oil, monoamine and diamine to 80-100 ℃ to enable amine liquid to be uniformly dissolved and have no granular feeling; mixing the two oil solutions at the temperature of 90-110 ℃ for reaction;
(2) heating the mixture to 140-160 ℃;
(3) adding 25% of base oil into the mixture for cooling, and cooling the mixture to 120-140 ℃;
(4) continuously heating the mixture to 200-220 ℃; adding additive when the mixture is cooled, and grinding into grease.
According to the preparation method of the tetraurea lubricating grease, in the step (1), the mixing reaction temperature is 95-105 ℃, and the mixing reaction time is 30-40 minutes. And (3) heating the mixture in the step (2) to 145-155 ℃, and keeping the temperature for 20-30 minutes. And (4) cooling the mixture in the step (3) to 125-135 ℃, and keeping the temperature for 20-30 minutes. And (4) heating the mixture to 205-215 ℃, keeping the temperature for 10-20 minutes, adding various additives when the mixture is cooled to 50-60 ℃, and grinding the mixture into grease when the mixture is cooled to room temperature.
The tetraurea lubricating grease provided by the invention has excellent comprehensive performance. Compared with diurea grease, the high-temperature-resistant and water-spraying-resistant diurea grease has better high-temperature resistance, water spraying resistance and roller stability; compared with the commercial tetraurea lubricating grease, the tetraurea lubricating grease has more outstanding high-temperature property, obviously relieves high-temperature hardening, and completely meets the lubricating requirements of harsh parts in the industries of metallurgy, mine, textile, food, printing and dyeing, papermaking and the like.
Detailed Description
Example 1:
7% of tetraurea thickening agent (prepared by the reaction of TDI, dodecylamine, cyclohexylamine and 1, 2-cyclohexanediamine); 93% base oil (70% mineral oil mixed with 23% PAO synthetic oil); additive 1% (composed of antirust).
(1) Mixing 343g of 35% base oil and 32g of TDI, heating to 60 ℃ to fully dissolve the materials, simultaneously mixing 29g of dodecylamine, 3g of cyclohexylamine, 10g of 1, 2-cyclohexanediamine and 392g of 40% base oil, heating to 80 ℃ to uniformly dissolve amine liquid without granular sensation, and mixing the two oil liquids at 90 ℃ for reaction for 30 minutes;
(2) heating the mixture to 140 ℃ and keeping the temperature for 20 minutes;
(3) adding 245g of 25% base oil into the mixture, cooling, and keeping the temperature of the mixture at 120 ℃ for 20 minutes;
(4) all materials were warmed to 200 ℃ and thermostated for 10 minutes. When the temperature of the mixture is reduced to 50 ℃, 10g of 1 percent of antirust agent is added, and the mixture is ground into grease when the temperature is reduced to room temperature. The properties are shown in Table 1.
Example 2:
15% of tetraurea thickening agent (prepared by reacting 1, 6-hexamethylene diisocyanate, MDI, tetradecylamine, aniline and 1, 3-cyclopentediamine); 85% of base oil (70% of mineral oil and 15% of ester synthetic oil are mixed for use); additive 2% (consisting of 1% extreme pressure agent and 1% antiwear agent).
(1) Mixing 350g of 35% base oil with 32g of 1, 6-hexamethylene diisocyanate and 48g of MDI, heating to 80 ℃ to fully dissolve the materials, simultaneously mixing 73g of tetradecylamine, 4g of aniline, 19g of 1, 3-cyclopentyldiamine and 400g of 40% base oil, heating to 100 ℃ to uniformly dissolve the amine liquid without granular feeling, and mixing the two oil liquids at 110 ℃ for reacting for 40 minutes;
(2) heating the mixture to 160 ℃ and keeping the temperature for 30 minutes;
(3) adding 250g of 25% base oil into the mixture, cooling, and keeping the temperature of the mixture at 140 ℃ for 30 minutes;
(4) all materials were warmed to 220 ℃ and thermostated for 20 minutes. When the mixture is cooled to 60 ℃, 12g of 1 percent extreme pressure agent and 12g of 1 percent antiwear agent are added, and the mixture is ground into grease when cooled to room temperature. The properties are shown in Table 1.
Example 3:
10% of tetraurea thickener (prepared by reacting MDI, octadecylamine, hexadecylamine and 4, 4' -dicyclohexylmethane diamine); 90% base oil (60% mineral oil and 30% vegetable oil mixed for use); additive 1% (composed of antioxidant).
(1) 315g of 35 percent base oil and 40g of MDI are mixed and heated to 70 ℃ to fully dissolve the materials, meanwhile, 34g of octadecylamine, 8g of hexadecylamine, 17g of 4, 4' -dicyclohexyl methane diamine and 360g of 40 percent base oil are mixed and heated to 90 ℃ to uniformly dissolve amine liquid without granular sensation, and then the two oil liquids are mixed and reacted for 35 minutes at 100 ℃;
(2) heating the mixture to 150 ℃ and keeping the temperature for 25 minutes;
(3) adding 225g of 25% base oil into the mixture, cooling, and keeping the temperature of the mixture at 130 ℃ for 25 minutes;
(4) all materials were warmed to 210 ℃ and thermostated for 15 minutes. When the mixture is cooled to 55 ℃, 10g of 1 percent antioxidant is added, and when the mixture is cooled to room temperature, the mixture is ground into grease. The properties are shown in Table 1.
Example 4:
9% of tetraurea thickener (prepared by reacting 1, 4-cyclohexane diisocyanate, p-toluidine and 1, 2-cyclohexanediamine); 91% base oil (80% mineral oil mixed with 11% alkyl naphthalene synthetic oil); additive 1% (consisting of antiwear agent).
(1) Mixing 350g of 35% base oil and 50g of 1, 4-cyclohexane diisocyanate, heating to 65 ℃ to fully dissolve the materials, simultaneously mixing 32g of p-toluidine, 17g of 1, 2-cyclohexanediamine and 400g of 40% base oil, heating to 85 ℃ to uniformly dissolve amine liquid without granular sensation, and mixing the two oil liquids at 95 ℃ for reaction for 33 minutes;
(2) heating the mixture to 145 ℃ and keeping the temperature for 28 minutes;
(3) adding 250g of 25% base oil into the mixture, cooling, and keeping the temperature of the mixture at 125 ℃ for 23 minutes;
(4) all materials were warmed to 205 ℃ and thermostatted for 13 minutes. When the mixture is cooled to 53 ℃, 11g of 1 percent antiwear agent is added, and when the mixture is cooled to room temperature, the mixture is ground into grease. The properties are shown in Table 1.
Example 5:
12% of tetraurea thickening agent (prepared by reacting dicyclohexylmethane diisocyanate, octadecylamine, 4' -dicyclohexylmethane diamine and 1, 2-cyclohexanediamine); 88% of base oil (prepared by mixing 40% of PAO synthetic oil, 30% of ester synthetic oil, 10% of alkyl naphthalene synthetic oil and 8% of vegetable oil); and 4% of additive (consisting of 1% of antioxidant, 1% of extreme pressure agent, 1% of antiwear agent and 1% of antirust agent).
(1) Mixing and heating 371g of 35% base oil and 62g of dicyclohexylmethane diisocyanate to 75 ℃ to fully dissolve the materials, simultaneously mixing and heating 64g of octadecylamine, 12g of 4, 4' -dicyclohexylmethane diamine, 7g of 1, 2-cyclohexanediamine and 424g of 40% base oil to 95 ℃ to uniformly dissolve amine liquid without granular feeling, and mixing and reacting the two oil liquids at 105 ℃ for 38 minutes;
(2) heating the mixture to 155 ℃ and keeping the temperature for 22 minutes;
(3) adding 265g of 25% base oil into the mixture, cooling, and keeping the temperature of the mixture at 135 ℃ for 27 minutes;
(4) heating all the materials to 215 ℃, keeping the temperature for 17 minutes, cooling the mixture to 55 ℃, adding 12g of 1% antioxidant, 12g of 1% extreme pressure agent, 12g of 1% antiwear agent and 12g of 1% antirust agent, cooling to room temperature, and grinding into grease. The properties are shown in Table 1.
Comparative example 1:
a commercial tetraurea grease.
Comparative example 2:
commercial diurea greases.
TABLE 1 comparison of product Properties
As is apparent from Table 1, comparative examples 1 to 5 are all novel tetraurea greases and are excellent in overall performance. Comparing example 3 with comparative example 2, the tetraurea grease has better high temperature, water spray resistance and roller stability than the diurea grease. In comparative example 3 and comparative example 1, the high temperature properties of the novel tetraurea grease were more excellent than those of the commercially available tetraurea grease, and the high temperature hardening was significantly alleviated.
The tetraurea lubricating grease provided by the invention has excellent comprehensive performance, has more outstanding high temperature compared with commercial diurea and tetraurea lubricating grease, and completely meets the lubrication requirements of harsh parts in the industries such as metallurgy, mine, textile, food, printing and dyeing, papermaking and the like.
Claims (7)
1. A tetraurea grease comprising a tetraurea thickener and a base oil; the components and the parts by weight are as follows: tetraurea thickener: 7-15%; base oil: 85-93%; the tetraurea thickening agent is prepared by reacting monoamine, diamine and diisocyanate, wherein the weight ratio of monoamine: diamine (b): the molar ratio of the diisocyanate is 2:1:2, and the structural general formula is as follows:
wherein R is1Represents the end group of a monoamine, R2Represents a middle group of a diisocyanate, R3Represents a diamine intermediate group;
the diamine is 4, 4' -dicyclohexylmethane diamine;
the monoamine is R1Is a carbon number C12～C18At least one of normal alkyl monoamine, cyclohexyl or cyclopentyl monoamine, phenyl or substituted phenyl monoamine, and the structural general formula is R1-NH2At least one of dodecylamine, tetradecylamine, hexadecylamine, octadecylamine, cyclopentylamine, cyclohexylamine, aniline, and p-toluidine;
the diisocyanate refers to aliphatic diisocyanate, alicyclic diisocyanate and aromatic diisocyanate and has a structural general formula of ONC-R2-CNO, which is at least one of 4,4 '-diphenylmethane diisocyanate (MDI), Toluene Diisocyanate (TDI), 1, 4-cyclohexane diisocyanate, p-phenylene diisocyanate, 4' -dicyclohexylmethane diisocyanate, and 1, 6-hexamethylene diisocyanate.
2. The tetraurea grease of claim 1 wherein the base oil is mineral oil, synthetic oil, vegetable oil or a mixture thereof.
3. The tetraurea grease of claim 1 wherein the base oil is mineral oil.
4. The tetraurea grease according to claim 1 wherein the monoamine is octadecylamine.
5. The tetraurea grease of claim 1 wherein the diisocyanate is MDI.
6. The process for preparing a tetraurea grease according to claim 1, which comprises the steps of:
(1) mixing 35% of base oil and diisocyanate, heating to 60-80 ℃, and fully dissolving the materials; then mixing and heating 40% of base oil, monoamine and diamine to 80-100 ℃ to enable amine liquid to be uniformly dissolved and have no granular feeling; mixing the two oil solutions at the temperature of 90-110 ℃ for reaction;
(2) slowly heating the mixture to 140-160 ℃;
(3) adding 25% of base oil into the mixture for cooling, and cooling the mixture to 120-140 ℃;
(4) continuously heating the mixture to 200-220 ℃; adding additive when the mixture is cooled, and grinding into grease.
7. The method according to claim 6, wherein the mixing reaction temperature in the step (1) is 95 to 105 ℃ and the mixing reaction time is 30 to 40 minutes; heating the mixture in the step (2) to 145-155 ℃ and keeping the temperature for 20-30 minutes; cooling the mixture in the step (3) to 125-135 ℃ and keeping the temperature for 20-30 minutes; heating the mixture in the step (4) to 205-215 ℃ and keeping the temperature for 10-20 minutes; and cooling the mixture to 50-60 ℃, adding various additives, cooling to room temperature, and grinding into grease.
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| CN112795418A (en) * | 2020-12-08 | 2021-05-14 | 青岛中科润美润滑材料技术有限公司 | Tetra-urea lubricating grease composition prepared from aromatic diamine and preparation method thereof |
| CN112899053B (en) * | 2021-01-22 | 2022-04-08 | 中国科学院兰州化学物理研究所 | Tetraurea thickening agent, application of tetraurea thickening agent in lubricating grease and preparation method of lubricating grease |
| CN116891771A (en) * | 2023-06-05 | 2023-10-17 | 武汉理工大学 | Polyurea grease and preparation method and application thereof |
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| EP1828356A1 (en) * | 2004-12-16 | 2007-09-05 | Shell Internationale Research Maatschappij B.V. | Lubricating grease composition |
| WO2008073773A1 (en) * | 2006-12-07 | 2008-06-19 | Shell Oil Company | Process and apparatus for preparing a urea grease |
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| CN103484225A (en) * | 2013-08-29 | 2014-01-01 | 中国石油化工股份有限公司 | High-temperature polyurea lubricating grease composition and preparation method thereof |
| CN104011190A (en) * | 2011-12-22 | 2014-08-27 | 国际壳牌研究有限公司 | Grease composition |
| CN108841430A (en) * | 2018-07-23 | 2018-11-20 | 中国石油化工股份有限公司 | A kind of compound urea aluminium-base grease composition and preparation method |
-
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- 2019-03-28 CN CN201910240560.7A patent/CN109913287B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1828356A1 (en) * | 2004-12-16 | 2007-09-05 | Shell Internationale Research Maatschappij B.V. | Lubricating grease composition |
| WO2008073773A1 (en) * | 2006-12-07 | 2008-06-19 | Shell Oil Company | Process and apparatus for preparing a urea grease |
| CN102382707A (en) * | 2010-08-31 | 2012-03-21 | 中国石油化工股份有限公司 | Tetra-urea lubricating grease and preparation method thereof |
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